Credit: The Associated Press

Portugal's Cristiano Ronaldo stops a ball during an official training session the day before the group G World Cup soccer match between Germany and Portugal at the Arena Fonte Nova in Salvador, Brazil, Sunday, June 15, 2014. (AP Photo/Paulo Duarte)

Credit: The Associated Press

United States' head coach Jurgen Klinsmann juggles a soccer ball before an official training session the day before the group G World Cup soccer match between Ghana and the United States at the Arena das Dunas in Natal, Brazil, Sunday, June 15, 2014.

Credit: The Associated Press

Ghana's Asamoah Gyan attends a press conference before an official training session the day before the group G World Cup soccer match between Ghana and the United States at the Arena das Dunas in Natal, Brazil, Sunday, June 15, 2014. (AP Photo/Dolores Ochoa)

Credit: The Associated Press

Nigerian players warm up during an official training session the day before the group F World Cup soccer match between Iran and Nigeria at the Arena da Baixada in Curitiba, Brazil, Sunday, June 15, 2014. (AP Photo/Frank Augstein)

Credit: The Associated Press

Iran players warm up during an official training session the day before the group F World Cup soccer match between Iran and Nigeria at the Arena da Baixada in Curitiba, Brazil, Sunday, June 15, 2014. (AP Photo/Frank Augstein)

RIO DE JANEIRO — Cristiano Ronaldo is ready to lead Portugal against Germany in one of the biggest games of the World Cup's first week, saying his sore knee won't be a problem.

The Real Madrid forward, arguably the most recognizable player in the sport, said he wouldn't risk his career by going into such a tough match with a serious injury. The match at Salvador features two of the top teams in the world, with Germany ranked No. 2 and Portugal at No. 4.